The amount of information and content available on the Internet continues to grow exponentially. Given the vast amount of information, search engines have been developed to facilitate searching for electronic documents. In particular, users may search for information and documents by entering search queries comprising one or more terms that may be of interest to the user. After receiving a search query from a user, a search engine identifies documents and/or web pages that are relevant based on the search query. Because of its utility, web searching, that is, the process of finding relevant web pages and documents for user issued search queries has arguably become the most popular service on the Internet today.
Many search queries are directed to particular entities or concepts, such as a particular person, place, or thing. When some search engines receive a search query from an end user, the search engines attempt to identify whether the search query refers to a particular concept. If so, the search engine may configure that search results returned to the end user based on the identified concept. However, some search queries may be ambiguous about which concept is intended. For instance, if a user submits the search query “kennedy birthday,” it would be ambiguous which kennedy the user intends. As another example, if a user submits the search query “java,” it's unclear whether the user intends the island, coffee, or the programming language.